2003 M45 Knock Sensor Recall?

[stroked347]

I was looking around the internet and came across the recall for the 2003 m45s for the knock sensor. Did anyone experience this problem? What exactly are the symptoms of a faulty/bad knock sensor?

(This is the first 'modern' car i've owned, old muscle cars previous to the M, so I don't know what a knock sensor does or how it affects the car if it's faulty)

[SteveTheTech]

Hey there and Welcome to NICO!

First off there is no recall for knock sensors and any of our vehicles. Below I have supplied a brief description of what exactly the knock sensor does.

DTC P0327, P0328, P0332, P0333 KS PFP:22060Component Description The knock sensor is attached to the cylinder block. It senses engineknocking using a piezoelectric element. A knocking vibration fromthe cylinder block is sensed as vibrational pressure. This pressure isconverted into a voltage signal and sent to the ECM.

[stroked347]

Steve,

Thanks for the info!

Another quick question, I recently started to experience small 'fluctuations' in the idle speed of my M45. We're talking a couple hundred rpm, almost unnoticable and the car runs/sounds great. Just one of those things you notice and it is bothering me...any ideas what might cause it or what to check?

Below is the recall I had come across...wasn't a knock sensor after all (i must've seen that for something else). This recall may have been a broad recall for all nissans....

2003 INFINITI M45 Recall ID from NHTSA: 03V455000 Auto Recall Date: NOV 17, 2003 Vehicle Component: ENGINE AND ENGINE COOLING Model Affected M45 Estimated Vehicles Affected: 630000 Recall Details

Auto Recall Date: NOV 17, 2003

Vehicle Component: ENGINE AND ENGINE COOLINGEstimated Vehicles Affected: 630000Model Affected2003 INFINITI M45

2003 Infiniti M45 Defect Summary:ON CERTAIN PASSENGER VEHICLES, THE CIRCUIT BOARD FOR THE CRANK POSITION SENSOR OR CAM POSITION SENSOR MAY HAVE AN IMPROPER SOLDER JOINT DUE TO SOLDER DEFORMATION CAUSED BY HEAT STRESS ACCELERATED BY THE EXISTENCE OF FLUX RESIDUE DURING THE SOLDERING PROCESS.

Defect Consequence:THIS COULD CAUSE THE "SERVICE ENGINE SOON" WARNING LIGHT TO COME ON, CREATE A NO START CONDITION, CAUSE REDUCED ENGINE POWER, OR CAUSE THE ENGINE TO STOP RUNNING WITHOUT WARNING DURING VEHICLE OPERATION, WHICH COULD RESULT IN A CRASH.

Remedy:DEALERS WILL REPLACE THE CRANK POSITION SENSORS. CAMSHAFT POSITION SENSOR(S), AND IN SOME CASES, THE VARIABLE TIMING CONTROL SENSOR(S). VEHICLES INVOLVED IN A PREVIOUS RECALL CAMPAIGN, 01V357, ARE ALSO INCLUDED IN THIS NEW CAMPAIGN. THE REPLACEMENT SENSORS USED IN THAT CAMPAIGN ARE ALSO AFFECTED. OWNER NOTIFICATION BEGAN ON DECEMBER 22, 2003. OWNERS SHOULD CONTACT NISSAN AT 1-800-647-7261 OR INFINITI AT 1-800-662-6200.

Estimated Vehicles Affected: 630000

Notes: NISSAN NORTH AMERICA, INC. R3021/R3022

[SteveTheTech]

If your car has been to the dealer at any point in the last five years that should have been taken care of. As recall lines are automatically generated on work orders.

I would check your oil level. If it is over full there is a chance that it was cause a vibration almost miss feeling at idle.

This is the recommended amount and viscousity rating.

VK45DEEngine Oil SAE 5W-30 (API SG, SH & Energy Conserving II)With Oil Filter 5 7/8 qtWithout Oil Filter 5 1/4 qt

[Double E]

The explanation for the knock sensor was dead-on but stopped short of describing what difference it makes once the "knocking" signal is sent to the ECU.

If you know muscle cars, this will be simple; Once the signal is sent that a knock is present, the timing is instantly adjusted to compensate for the knock.

This, as you know, retards timing and power to prevent the cylinder from slamming against an explosion already in progress or pre-detonation.

The knock sensor can only do so much though, so make sure there's the highest octane in the tank possible...that's readily available.

In short, we (the mere mortals without access to re-writing lines of code in the ECU) cannot set the timing on these cars on our own. Instead, it is set according to the conditions of fuel/air.

All of that being said, it is important to note that the sensor can go bad. In my '97 I30, the sensor was notorious for going bad at about 120K miles and it was a monster pain to replace. Because the sensor has to "listen" for knock, it is buried (on that car) deep in the V of the engine. Some people were able to access it by contorting their hands to get to it with a socket, and some had to remove the IM and God knows what else.

I think our M's have 2 of these sensors. (Maybe Shozain can verify?) and in any case, in my experience, if they go bad, they do not throw a CEL code but instead use a "safe" mode map that restricts the timing to "retard" no matter what fuel is used ...and thus performance is decreased. The only way you'd ever know it was bad was to remove the sensor and resistance-test them or if another CEL code appears, the knock sensor code will appear with it. In the VQ forums, they were called "ghost codes".

Hope this all helps...

[SteveTheTech]

The knock sensor is a detectable item, however it will not set a CEL, but will however store a P0327,P0328,P0332,orP0333 depending on what is wrong. The M does in fact have two sensors one for each bank and they are a pain to replace. I do not think that the K/S is the problem unless you have a stored DTC with no other codes. Usually they will activate with a P0300-P0308 or lean code.

I would recommend getting it looked at to avoid any damage. Plus any off statiometric running condition will have adverse effects on fuel economy.

[stroked347]

Steve and Double E,

Thanks for all the great info. I'm going to take the car in and get it looked at. Hopefully it's just an easy fix but i'll post my results once they look at it.

[Double E]

Stroked, Good plan.

I've not seen issues with our models yet concerning the KSon this motor, but few people have over 100000 miles here yet too. I would not give it concern unless the code pops up.

Keep the best octane you can get in it, give it the clean-out (WOT) procedure occasionally and love it. Toss in a can of BG44k every 10K miles.

[stroked347]

well, it seems the problem is fixed, for now at least. I figured I'd do an oil change and throw in some 44K before taking it in and that seems to have done the trick...the idle is back where it was before and the bouncing tach needle has vanished. I've always changed the oil every 3750 miles for the 3 yrs i've had it (since 27k) and occasionally use the 44k, so i don't know what to think. I recently had the common fuel gauge problem and had the fuel sending unit replaced along w/ a new gauge cluster so maybe that messed w/ something

thanks again for all the help

[SteveTheTech]

I would put money on there being too much oil, I am glad it's fixed though it's good to have another local well running M.

It sounds like you have taken good care of it.

[stroked347]

yeh, thinking back to about when it started, i did 'top' up the oil on a roadtrip and probably didn't let the oil settle enough before checking the dipstick. I'm suprised it would have that much effect but considering the 20w50 oil(like molasses) i use in my mustang, i guess i can see it happening.

ya live and learn and luckily it seems to be working now...plus, i learned what a knock sensor does!